Cooling System: Description and Operation
Engine CoolingCAUTION: Vehicle cooling systems are filled with Motorcraft Premium Gold Engine Coolant (yellow color). Always fill the cooling system with the same type of coolant that was drained from the system. Do not mix coolant types. Mixing coolant types degrades the corrosion protection of Motorcraft Premium Gold Engine Coolant, and may result in damage to the cooling system.
NOTE: The addition of Cooling System Stop Leak Pellets darkens Motorcraft Premium Gold Engine Coolant from yellow to golden tan.
The cooling system consists of the:
^ Block heater
^ Coolant crossover manifold assembly (4.6L, 5.4L)
^ Degas bottle
^ Fan blade
^ Mechanical fan clutch (4.2L)
^ Electronic fan clutch (4.6L, 5.4L)
^ Fan shroud
^ Radiator
^ Pressure relief cap
^ Radiator draincock
^ Upper and lower radiator hoses
^ Coolant pump
^ Coolant thermostat
The block heater:
^ warms the coolant during extreme cold weather conditions.
^ uses 110V AC electrical source.
The coolant crossover manifold:
^ provides for coolant flow between the cylinder heads.
^ houses the thermostat.
^ has an attachment for the heater hose.
The degas bottle:
^ holds surplus coolant when hot.
^ de-aerates the system reducing hot spots.
^ is the location for service fill.
^ allows coolant expansion and system pressurization.
^ replenishes coolant to the system.
The fan blade draws air through the radiator to help cool the system coolant.
The fan clutch controls the fan speed.
The fan shroud directs air flow through the radiator
The radiator:
^ allows excess heat to be transferred to the air.
^ cannot be serviced. Install a new radiator.
The pressure relief cap:
^ provides for cooling system pressurization.
^ is the location for service fill.
The radiator draincock:
^ provides for cooling system draining.
The radiator hoses:
^ allow coolant flow between the engine and the radiator
The coolant pump:
^ circulates the coolant.
The coolant thermostat:
^ controls coolant temperature.
^ allows quicker engine warm-up.
The engine coolant flows:
^ from the lower radiator hose to the coolant pump.
^ from the coolant pump to the engine block, the cylinder heads, heater core and PCV fittings.
^ thermostat closed, the coolant returns to the coolant pump.
^ thermostat open, the coolant flows back to the radiator for heat rejection.
CAUTION: Engine coolant provides freeze protection, boil protection, cooling efficiency and corrosion protection to the engine and cooling components. In order to obtain these protections, the engine coolant must be maintained at the correct concentration and fluid level in the degas bottle, or the engine may be damaged.
NOTE: The addition of Cooling System Stop Leak Pellets darkens Motorcraft Premium Gold Engine Coolant from yellow to golden tan.
When adding engine coolant, use a 50/50 mixture of engine coolant and distilled water.
To maintain the integrity of the coolant and the cooling system:
^ Add Motorcraft Premium Gold Engine Coolant (yellow color). Do not mix coolant types.
^ Do not add orange-colored Motorcraft Specialty Orange Engine Coolant. Mixing coolants may degrade the coolant's protection rating.
^ Do not add alcohol, methanol or brine or any engine coolants mixed with alcohol or methanol antifreeze. These can cause engine damage from overheating or freezing.
^ Do not mix with recycled coolant. Use of such a coolant may harm the engine and cooling system components.
Coolant Flow Diagram, 4.2L (Part 1):
Coolant Flow Diagram, 4.2L (Part 2):
Coolant Flow Diagram, 4.6L (2V) (Part 1):
Coolant Flow Diagram, 4.6L (2V) (Part 2):
Coolant Flow Diagram, 5.4L (3V) (Part 1):
Coolant Flow Diagram, 5.4L (3V) (Part 2):
